In this application, three NIH investigators are requesting funds for an electron spectroscopy for chemical analysis (ESCA) instrument. This type of instrumentation, widely used in the physics and microelectronics communities, will be applied to the analysis of the surface structure and composition (outermost 50A) of synthetic materials used in clinical and experimental implants, adsorbed protein films, and cell surfaces. The principal investigator on this application is also the principal investigator of an NIH Division of Research Resources (DRR) instrumentation resource -- the National ESCA and Surface Analysis Center for Biomedical Problems (NESAC/BIO). NESAC/BIO was recently refunded for five years. Because of heavy use of the existing ESCA instrument, the NIH study section recommended that an application be made to the SIG program for a new instrument. Significant matching funds from both the DRR and the University of Washington have been provided. This new instrument will be used in the research programs of the core investigators of NESAC/BIO. External users of NESAC/BIO will continue to use the existing instrument. Specific research projects in this application include endothelial cell growth, protein adsorption, orthopaedic and dental implant corrosion, polyurethanes for artificial hearts and vascular grafts, cell-surface studies, platelet interactions with synthetic polymers, nonfouling surfaces, and vascular grafts that exhibit low platelet interaction.